shiqiu1105 wrote:I don't understand. If Timo Aila's work is the state of the art of gpu ray tracing, then why don't dicuss that in the thesis, instead talk about path regeneration and stream path tracing??

It is briefly discussed in 6.1.1. Thing is, Aila & Laine provide ray traversal kernels which are state-of-the-art, and this is used as a building block in many other algorithms, including path regeneration and streaming path tracing. It's basically a low-level block that I take for granted, and build upon.